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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Effect of dietary fat source on fat utilization by the young pig.

Hamilton, R. M. G. January 1968 (has links)
No description available.
322

Studies on the influence of different planes of nutrition on Haemonchus contortus infection in lambs.

Hamza, František. January 1968 (has links)
No description available.
323

Feeding behaviour of the guppy, Poecilia reticulata (Pisces : Poeciliidae)

Dussault, Gertrude V. January 1980 (has links)
No description available.
324

Microencapsulation of water-soluble substances for delivery to marine bivalves

Buchal, Michael A. 12 December 1994 (has links)
A new method for encapsulating low-molecular weight, water-soluble substances in lipid-walled microcapsules (LWMs) for delivery to marine bivalves was developed, characterized, and tested. LWMs produced by a spray technique (spray microcapsules, SMs) were demonstrated to encapsulate both aqueous (polymeric dye or oxytetracycline hydrochloride) and particulate (riboflavin) core materials within a capsule wall composed of triacylglycerides. Core materials were most effectively delivered in a capsule wall composed of tripalmitin. Addition of lower melting point lipids to soften the capsule wall significantly reduced (up to a nine-fold reduction) delivery of aqueous core materials, but did not significantly affect particulate riboflavin delivery. The composition of the capsule wall was demonstrated to affect the digestibility of LWMs. Addition of 40% w/w fish oil to the tripalmitin wall was required for Manila clam spat (Tapes philippinarum) enzymatically digest LWMs (convert triaclyglycerides to free fatty acids). Delivery of aqueous and particulate core materials by microcapsules was assessed by feeding clams LWMs containing an aqueous core of polymeric dye or a particulate core of oxytetracycline hemicalcium salt (OTC.HEM). The physical appearance and absence of core material in capsules observed in clam fecal strands suggested release and delivery of core materials in the clam's digestive system. Optimal methods for encapsulating and storing oxytetracycline were assessed. Oxytetracycline hydrochloride was most efficiently encapsulated (3.2 mg core/ 100 mg lipid) and retained (30%) as an aqueous core in LWMs produced by a double-emulsion process (double-emulsion microcapsules, DEMs). OTC.HEM was most efficiently encapsulated (7.4 mg core/l00 mg lipid) and retained (66% of initial encapsulated core material remained after 24 hours suspension in seawater) as a particulate in SMs. SMs containing OTC.HEM were most stable in storage, retaining 86% of their core after 5 weeks of storage as a wet paste. Freeze-drying of SMs containing particulate OTC.HEM increased initial leakage losses of core material, but did not the affect the stability of capsules during long-term storage. Freeze-drying of DEMs containing aqueous OTC.HCl also increased initial leakage loses of core material, but improved the stability of DEMs during long-term storage. / Graduation date: 1995
325

Management and marketing strategies for high desert beef ranches in Eastern Oregon

Panasuk, Eugene Duane 21 October 1971 (has links)
Ranchers in the high desert area of Eastern Oregon traditionally market their calves when they are weaned in late fall. This is the time when the market prices for calves are at a seasonal low. In this study the economic feasibility of various alternative management and marketing strategies for the utilization of range forage with a spring calving operation is determined. The operational objectives were (1) to determine the most profitable time and weight to market the spring-born calves, (2) to determine whether supplementary feeding of yearlings is economically feasible, (3) to explore the competitive relationship between cows and yearlings for limited range forage, and (4) to determine the combination of beef production and growing activities which will provide the highest net returns. Linear programming was used to determine the combination of activities that would maximize net returns subject to the constraint of forage quality and quantity. The quality and quantity of the range forage was determined by using data provided by the Squaw Butte Experiment Station, Burns, Oregon. All the basic data pertaining to the high desert area were obtained from Squaw Butte. The initial L. P. solution indicated the heifers should be sold March 1 at 600 pounds having been fed to gain 1.5 pounds per day while the steers were sold April 16 at 780 pounds, gaining 2.0 pounds per day. The cows earned a higher MVP for the limited resource, range forage, than could the yearlings either with or without supplementary feeding. In the second solution barley price was reduced from $50 to $45 per ton and the steers were sold April 16 at 780 pounds (same as initial solution). The heifers were sold June 16 weighing 900 pounds having been fed to gain 2.0 pounds per day. Supplementary feed was provided on the range for these heifers from April 16 to June 15. The study shows that the traditional management and marketing practice is not the most profitable alternative. The feed costs are less than the increase in income from feeding the animals to heavier weights. / Graduation date: 1972
326

Parental use of child feeding practices and outcomes in child and adolescent nutrition

Yeley, Genevieve Connors 17 February 2005 (has links)
The incidence of childhood and adolescent overweight in the United States is increasing at an alarming rate and is now considered the most prevalent nutritional disease of children and adolescents in this country. Although much attention has focused on genetic research, and heredity is an unarguable component of obesity, the role of the environment must be considered because genetic changes over entire populations are not likely to occur at such a rapid rate. In observing today’s environment where energy-dense foods abound, restaurant dining has increased, and children are more sedentary than ever, the current trends in child/adolescent weight status are not surprising. This study digs to the heart of worrisome eating habits by exploring the development of these behaviors in the family. Previous studies show that parents’ use of child feeding practices is related to their children’s weight status. It is hypothesized that children of parents who utilize highly controlling feeding strategies (pressure, restriction, monitoring) will have nutrient intakes and weight indicators that are either higher or lower than the average for children whose parents exert less control over the eating domain. The objective of this research is to discover if significant relationships exist between parental child feeding strategies and child/adolescent overweight or underweight and nutrient intake. Birch’s model explaining familial resemblances in eating and weight status was tested using her previously validated Child Feeding Questionnaire, standard anthropometric techniques, three days of diet records, and a previously validated child questionnaire. Three-hundred and twelve children/adolescents, 254 mothers, and 245 fathers from the Houston Metropolitan Statistical Area completed interviews, and data was analyzed with the Statistical Analysis System (SAS). Results confirmed the validity of Birch’s model and previous studies that found significant relationships between child feeding strategies and children’s nutrition status. Parents who pressured their children to eat (motivated by concern about the child being underweight) were more likely to have children with lower BMI percentiles and skinfolds while parents who monitored or restricted the child’s intake had children with higher BMI percentiles and skinfold thicknesses. No clear relationships were found between feeding styles and nutrient intake.
327

Early detection of morbidity in feedlot cattle using pattern recognition techniques

Silasi, Reka 18 December 2007
Computer algorithms are routinely used to aid in the identification of biological patterns not easily detected with standard statistics. Currently, observed changes in normal patterns of feeding behavior (FB) are used to identify morbid feedlot cattle. The objective of this study was to use pattern classification techniques to develop algorithms capable of identifying morbid (M) cattle earlier than traditional pen checking methods. In two separate studies, individual feeding behaviour was obtained from 384 feedlot steers (228 ± 22.7 kg, initial BW) in a 226 d trial (model dataset), and 384 feedlot heifers (322 ± 34.7 kg, initial BW) in a 142 d trial (naive dataset). Data was collected using an automated feed bunk monitoring system. FB variables calculated included feeding duration, inter-meal interval (min., max., avg., SD and total; min/d) and feeding frequency (visits/d). Animal health records including the number of times treated, d in the hospital and d on feed were also collected. Ninety-three and 53 morbid (M) animals were identified in each trial respectively, and were categorized into low, moderate and high groups, based on severity of sickness. FB data for 68 cattle from the model dataset (45 classified as Moderate and 25 classified as High) was analyzed to develop an algorithm which would aid in identifying morbid FB. This algorithm was later tested on 18 M animals (12 classified as Moderate and 6 as High) in the naive dataset. The pattern recognition procedure involved reducing data dimensionality via Principal Component Analysis, followed by K-means clustering and finally the development of a binary string to aid in the classification of M feeding behaviour. The developed procedure resulted in an overall classification accuracy of 84 % (82.5 and 85 % accuracy for H and M, respectively) for the model dataset, and 75 % overall (100 and 50 % accuracy for H and M, respectively) for the naive dataset. The model predicted morbidity on average 3.3 and 1.2 d earlier than pen checkers could for each trial respectively. The application of pattern recognition algorithms to FB shows value as a method of identifying morbid cattle in advance of overt physical signs of morbidity.
328

Early detection of morbidity in feedlot cattle using pattern recognition techniques

Silasi, Reka 18 December 2007 (has links)
Computer algorithms are routinely used to aid in the identification of biological patterns not easily detected with standard statistics. Currently, observed changes in normal patterns of feeding behavior (FB) are used to identify morbid feedlot cattle. The objective of this study was to use pattern classification techniques to develop algorithms capable of identifying morbid (M) cattle earlier than traditional pen checking methods. In two separate studies, individual feeding behaviour was obtained from 384 feedlot steers (228 ± 22.7 kg, initial BW) in a 226 d trial (model dataset), and 384 feedlot heifers (322 ± 34.7 kg, initial BW) in a 142 d trial (naive dataset). Data was collected using an automated feed bunk monitoring system. FB variables calculated included feeding duration, inter-meal interval (min., max., avg., SD and total; min/d) and feeding frequency (visits/d). Animal health records including the number of times treated, d in the hospital and d on feed were also collected. Ninety-three and 53 morbid (M) animals were identified in each trial respectively, and were categorized into low, moderate and high groups, based on severity of sickness. FB data for 68 cattle from the model dataset (45 classified as Moderate and 25 classified as High) was analyzed to develop an algorithm which would aid in identifying morbid FB. This algorithm was later tested on 18 M animals (12 classified as Moderate and 6 as High) in the naive dataset. The pattern recognition procedure involved reducing data dimensionality via Principal Component Analysis, followed by K-means clustering and finally the development of a binary string to aid in the classification of M feeding behaviour. The developed procedure resulted in an overall classification accuracy of 84 % (82.5 and 85 % accuracy for H and M, respectively) for the model dataset, and 75 % overall (100 and 50 % accuracy for H and M, respectively) for the naive dataset. The model predicted morbidity on average 3.3 and 1.2 d earlier than pen checkers could for each trial respectively. The application of pattern recognition algorithms to FB shows value as a method of identifying morbid cattle in advance of overt physical signs of morbidity.
329

Study on the feeding activity of Cerithium zonatum (Gastropoda:Mesogastropoda) by an acoustic approach

Hsu, Shi-lin 06 September 2010 (has links)
This study focused on a small gastropoda, Cerithium zonatum, found in seagrass meadow at Gui Wan Bi, Green Island, Taiwan. Because this species is high in density in the seagrass meadow and it uses its specific radular to scrap the substrate and emits a particular sound, we can use this acoustic clue to study its feeding activity. C.zonatum samples were collected from Gu Wan Bi, and Zi-Ping Green Island between November to December 2007,March to June 2008, and April to July 2009. It distributes in three habitats (i.e. seagrass¡Bmacro algae¡Brubble) and scrapping sounds were recorded while they were in these habitats. Light and water temperature were treated as experimented factors and their influence on the feeding frequency was deciphered. I also compared individuals of different sizes to find out the differences in feeding frequency between them. SEM was used to observe the radular of C. zonatum. According to the results, I infer that C. zonatum might prefer seagrass meadow as its must suitable microhabitat where feeding activity was higher. Sunlight and high water temperature might lead to increases in feeding activity, but darkness and low water temperature showed opposite effect; it stopped feeding when water temperature had dropped to 17¢J. Scrap frequency of small individuals was higher than larger ones, and their radular were similar in their morphology. I infer that small ones invest more time and energy in feeding in order to grow. Scrapping sound of C.zonatum was compared to Nerita albicilla; there were pulses in the sound of N.albicilla than C. zonatum. It is inferred that this difference might be due to the difference between their radular morphology. I consider that using an bioacoustic approach to study the feeding activity of small gastropoda is feasible.
330

Parental use of child feeding practices and outcomes in child and adolescent nutrition

Yeley, Genevieve Connors 17 February 2005 (has links)
The incidence of childhood and adolescent overweight in the United States is increasing at an alarming rate and is now considered the most prevalent nutritional disease of children and adolescents in this country. Although much attention has focused on genetic research, and heredity is an unarguable component of obesity, the role of the environment must be considered because genetic changes over entire populations are not likely to occur at such a rapid rate. In observing today’s environment where energy-dense foods abound, restaurant dining has increased, and children are more sedentary than ever, the current trends in child/adolescent weight status are not surprising. This study digs to the heart of worrisome eating habits by exploring the development of these behaviors in the family. Previous studies show that parents’ use of child feeding practices is related to their children’s weight status. It is hypothesized that children of parents who utilize highly controlling feeding strategies (pressure, restriction, monitoring) will have nutrient intakes and weight indicators that are either higher or lower than the average for children whose parents exert less control over the eating domain. The objective of this research is to discover if significant relationships exist between parental child feeding strategies and child/adolescent overweight or underweight and nutrient intake. Birch’s model explaining familial resemblances in eating and weight status was tested using her previously validated Child Feeding Questionnaire, standard anthropometric techniques, three days of diet records, and a previously validated child questionnaire. Three-hundred and twelve children/adolescents, 254 mothers, and 245 fathers from the Houston Metropolitan Statistical Area completed interviews, and data was analyzed with the Statistical Analysis System (SAS). Results confirmed the validity of Birch’s model and previous studies that found significant relationships between child feeding strategies and children’s nutrition status. Parents who pressured their children to eat (motivated by concern about the child being underweight) were more likely to have children with lower BMI percentiles and skinfolds while parents who monitored or restricted the child’s intake had children with higher BMI percentiles and skinfold thicknesses. No clear relationships were found between feeding styles and nutrient intake.

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